package Lee_code;

public class Lee_70_2 {
    public int climbStairs(int n) {
        int[] dp = new int[n+1];
        // 递推公式: dp[n] = dp[n-1] + dp[n-2];
        dp[0] = 0;
        dp[1] = 1;
        dp[2] = 2;
        for (int i=3; i<=n; i++)
        {
            dp[i] = dp[i-1] + dp[i-2];
        }
        return dp[n];
    }
}
